Boechera constancei

(Rollins) Al-Shehbaz

Novon 13: 384. 2003.

Basionym: Arabis constancei Rollins Contr. Gray Herb. 201: 5, plate 1. 1971
Synonyms: Arabis suffrutescens var. perstylosa Rollins
Treatment appears in FNA Volume 7. Treatment on page 371. Mentioned on page 351.

Perennials; long-lived; sexual; caudex woody. Stems usually 1 per caudex branch, arising from center of rosette, elevated above ground surface on woody base, 1.2–3 dm, glabrous throughout. Basal leaves: blade narrowly oblanceolate, 1.5–4 mm wide, margins entire, ciliate, trichomes (simple, mixed with fewer stalked, 2-rayed), 0.3–0.8 mm, surfaces glabrous. Cauline leaves: 6–12, not concealing stem; blade auricles absent, surfaces of distalmost leaves glabrous. Racemes 5–15-flowered, unbranched. Fruiting pedicels arched, strongly recurved proximally, 4–12 mm, glabrous. Flowers divaricate-ascending at anthesis; sepals glabrous; petals creamy white, 6–8 × 1.5–2 mm, glabrous; pollen ellipsoid. Fruits pendent, not appressed to rachis, usually secund, straight or slightly curved, edges often somewhat undulate (not parallel), 4–7.5 cm × 3–3.5 mm; valves glabrous; ovules 18–28 per ovary; style 2.5–5 mm. Seeds uniseriate, 3–4 × 2.5–3 mm; wing continuous, 0.5–1 mm wide. 2n = 14.


Phenology: Flowering May.
Habitat: Steep ridges, serpentine slopes
Elevation: 1200-1900 m

Discussion

Boechera constancei was originally treated as a variety of Arabis (Boechera) suffrutescens; it is easily separated from that species by its non-auriculate cauline leaf blades, longer (6–8 versus 4.5–6 mm) petals that are creamy white (versus purple or rose-tipped), much longer style (2.5–5 versus 0.4–1.2 mm), and exerted anthers. This distinctive sexual diploid is thus far known only from the west slope of the Sierra Nevada in Plumas County.

Selected References

None.

Lower Taxa

None.

"elongated" is not a number."thick" is not a number."dm" is not declared as a valid unit of measurement for this property.

... more about "Boechera constancei"
oblong +  and ovate +
Ihsan A. Al-Shehbaz +  and Michael D. Windham +
(Rollins) Al-Shehbaz +
not +  and rosulate +
Arabis constancei +
appendaged +  and unappendaged +
not +  and auriculate +
lyrate-pinnatifid +, dentate +  and entire +
dissected +, repand +, sinuate +, crenate +  and dentate +
oblanceolate +
much smaller +  and reduced +
0.15 cm1.5 mm <br />0.0015 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
urceolate +, campanulate +  and tubular +
branched +  and simple +
petiolate +  and sessile +
well-developed +
indistinct +
not +  and differentiated +
emarginate +  and entire +
4 cm40 mm <br />0.04 m <br /> (7.5 cm75 mm <br />0.075 m <br />) +
undulate +
0.3 cm3 mm <br />0.003 m <br /> (0.35 cm3.5 mm <br />0.0035 m <br />) +
1200-1900 m +
straight +  and curved +
not winged +  and unappendaged +
connate +  and distinct +
actinomorphic +
divaricate-ascending +
curved +  and straight +
torulose +, falcate +, lanceolate +, oblong +  and linear +
Steep ridges, serpentine slopes +
annular +  and semiannular +
sessile +  and petiolate +
alternate +, not +  and rosulate +
cauline +  and basal +
connate +  and distinct +
decurrent +
pinnatifid +
prominent +  and obscure +
tenuinucellate +, crassinucellate +  and bitegmic +
campylotropous +  and anatropous +
creamy white +
rudimentary +
oblanceolate +  and spatulate +
0.15 cm1.5 mm <br />0.0015 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
Flowering May. +
trinucleate +  and 3(-11)-colpate +
ellipsoid +
unbranched;5-15-flowered +
slender +
0.4 cm4 mm <br />0.004 m <br /> (1.2 cm12 mm <br />0.012 m <br />) +
mucilaginous +
margined +, not winged +  and winged +
biseriate +, sub-biseriate +  and uniseriate +
not +  and mucilaginous +
white +, black +, brown +  and yellow +
0.3 cm3 mm <br />0.003 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
orbicular +, oblong +  and flattened +
0.25 cm2.5 mm <br />0.0025 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
persistent +  and caducous +
distinct +
spreading +, ascending +  and erect +
oblong +  and ovate +
reduced +
latiseptate +, schizocarpic +, samaroid +  and lomentaceous +
indehiscent +  and dehiscent +
angustiseptate +, flat +, angled +, terete +, torulose +, not +, segmented +  and nutletlike +
tetradynamous +
branched +  and unbranched +
procumbent +  and decumbent +
subsessile +, sessile +  and petiolate +
persistent +
distinct +
0.25 cm2.5 mm <br />0.0025 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
Arabis suffrutescens var. perstylosa +
Boechera constancei +
Boechera +
species +
dendritic +, branched +  and simple +
0.03 cm0.3 mm <br />3.0e-4 m <br /> (0.08 cm0.8 mm <br />8.0e-4 m <br />) +
coiled +, 1-7-veined +  and veined +
anastomosing +
perennial +  and long-lived +
hispid +, hirsute +, pubescent +  and glabrous +
rhizomatous +, taprooted +, scapose +  and not +
perennial +, biennial +  and annual +
subshrub +  and herb +
aquatics +  and terrestrial +
glabrous +  and pubescent +
0.5mm;1mm +